Extrusion printing of carbon nanotube-coated elastomer fiber with microstructures for flexible pressure sensors

Microstructured wearable pressure sensors with high sensing performance have promising applications in soft robots, wearable electronics, and biomedical devices. However, current methods for the fabrication of the devices are complex, cost-ineffective, or time-consuming. Inspired by the crystalline ice plant having tiny crystalline beads on its stem, an extrusion printing method is developed to prepare carbon nanotube (CNT)-coated microstructured elastomer fibers for resistive and capacitive wearable pressure sensors. Due to the microstructures on the CNT-coated elastomer fiber, the resistive device has a sensitivity eight times higher than the smooth one, with a fast response time (20 ins), and a detectable limit of similar to 5.0 Pa. The capacitive device constructed using CNT-coated microstructured elastomer fiber provides a highest sensitivity of 0.17 kPa(-1), a response time around 25 ms, and a detectable limit of 0.02 kPa. The microstructured elastomer fiber based devices demonstrate the ability in measuring various external stimuli, exhibiting the potential for the aforementioned applications. (C) 2019 Elsevier B.V. All rights reserved.